GABA stimulates the rabbit corneal endothelial fluid pump.

GABA and its analogues were shown to activate the rabbit corneal endothelial fluid pump in the micromolar range. The stimulation was abolished by bicuculline and chlorpromazine, but not by picrotoxin.     

Brain catecholamines and organ weight of mice genetically selected for high and low blood pressure.

Statistically significant differences were found between the high and low genetically selected blood pressure lines for systolic blood pressure, norepinephrine content of whole brain, absolute heart weight, heart to b. wt ratio, kidney weight, kidney to b. wt ratio, and adrenal to b. wt ratio.     

The effect of age on cardiac output and its distribution in the rat.

Cardiac output distribution in the rat was found to be affected by age. Cardiac index and blood flow to the liver, kidneys, skin and skeletal muscle were lower in 11-12 month compared to 3-4 month old rats.     

Changes in beta-2 adrenergic receptor sensitivity with maturation of erythroid progenitor cells.

Erythroid burst forming units (BFU-E) were much more sensitive to the beta-2 selective adrenergic drug, salbutamol, than erythroid colony forming units (CFU-E) in an in vitro study of erythroid progenitor cells.     

Role of ACTH on the cytomorphology of testes of the immature rat.

The male gametogenic development of the immature rat shows inhibitory effect by the exogenous infusion of ACTH (0.25 IU and 0.50 IU; i.p.). Seminiferous tubular degeneration, Leydig cell atrophy and Sertoli cell regression are very conspicuous in the dosage of 0.50 IU ACTH (i.p.). Cytometrical and histological evidence confirms that ACTH could be inhibited by FSH during male gametogenic development which leads to cellular degeneration of testes in the immature rat.     

Corticosteroidogenesis by isolated human adrenal cells: effect of serotonin and serotonin antagonists.

The direct effect of serotonin and antiserotonin agents on adrenal steroid biosynthesis was studied in isolated adrenal cells derived from patients with Cushing's syndrome. The results indicate that serotonin increases corticosterone production, while the serotonin antagonists cyproheptadine and methysergide depress adrenal steroid - particularly cortisol and aldosterone - biosynthesis.     

ACTH-induced hyperalgesia in rats.

The injection of ACTH 1--24 into the cerebral ventricles in rats markedly reduces the reaction time in the hot-plate test and the nociception threshold in the tail-stimulation test. Morphine antagonizes and naloxone potentiates this hyperalgesic effect of ACTH. It is proposed that ACTH peptides play a physiological role in nociception.     

Absence of dopamine sensitive adenylate cyclase in the A10 region, the origin of mesolimbic dopamine neurones.

Dopamine (DA) failed to stimulate the adenylate cyclase of the mesolimbic A10 DA nerve cell body area, in contrast to tis activating effect in the nigrostriatal A9 DA cell body area. The enzyme was stimulated by GMPPNP (a GTP analog) and NaF. This indicates the absence in the A 10 cell area of DA receptors with functional coupling on adenylate cyclase, in contrast to the A9 cell area where such DA receptors are believed to be located on afferent axon terminals.     

A species comparison of 2,4-dinitrotoluene metabolism in vitro.

Postmitochondrial supernatants prepared from livers of mice, rats, rabbits, dogs, and monkeys metabolized 2,4-dinitrotulene. The pattern of metabolites was characterized in both sexes of the species examined. In addition, the pattern of metabolites was altered by varying incubation conditions and pretreating male rats with phenobarbital or SKF 525-A.     

Criteria for the appearance of post-tetanic potentiation of transmission at central synapses in Helix aspersa.

Long-lasting potentiation of inhibitory post-synaptic potentials occurs at 2 identifiable synapses in Helix brain. It appears only after tetanic stimulation and after a minimum of 20 impulses. Its amplitude and duration depends on the number of stimuli.